Clinical recommendation	Evidence rating	References
The diagnosis of psoriasis usually is based on the clinical appearance of the skin lesions.	C	35
Topical steroids and calcipotriene (Dovonex) are the mainstays of topical therapy and, when used together, they may work better than either agent alone.	A	17,18,29,30
Patients who have psoriasis involving more than 20 percent of their skin are candidates for light therapy or systemic therapy, and usually these patients are managed in conjunction with a dermatologist.	C	30,35